1. Field of the Invention
The invention relates to a daylight-loading film sheet package which comprises a stack of film sheets light-tightly wrapped in a light-shielding wrapper, and a method for the production of such wrapper.
Film sheet packages of the described kind are used in medical X-ray departments where a filmcassette loader, or a combined filmcassette unloader/loader is provided for removing in daylight conditions an image-wise exposed film sheet from a film cassette and conveying it to a film processor, and for reloading the emptied cassette with a fresh film of the appropriate format taken from a corresponding magazine with fresh film sheets. The loading of the magazine with fresh film sheets may occur in the darkroom, but a far more convenient method is to load the magazine in daylight conditions by means of an appropriate daylight-loading film sheet package. In this way, the photographic process may be completely carried out without need for a darkroom.
2. Description of the Art
A film sheet package of the described type is disclosed in EU A1 0 313 686 entitled "Film sheet package and method of packaging filmsheets". In this publication there is disclosed a daylight-loading filmsheet package for use with a magazine which comprises a box with a light-tight lid and a winding mechanism at the frontside for pulling the wrapper from a film sheet package contained in the magazine thereby to set the film sheet stack free for removal of the film sheets from the stack, one by one, through the opened lid by a suitable removal mechanism. The film sheet package comprises a stack of film sheets wrapped in a light-tight sleeve that has a closed flap at one end which is arranged for being gripped and wound by the winding mechanism of the magazine, and that has at the opposite end an open flap folded back to light-tightly close the film package.
The mentioned package shows the disadvantage that the complete removal of the wrapping produces a rather voluminous roll of wrapping material which requires extra space in the magazine. Also, the removal of the complete wrapper requires considerable force from the winding mechanism.
A film sheet package of a different type is disclosed in EU A2 0 215 427 entitled "Sheet film package and method and device for loading sheet film". This publication discloses a film sheet package comprising a tray with lips at its top surface to which a flexible cover member is peelably attached.
This construction offers the advantage that only the cover must be removed from the package to provide access to the film sheets. The co-operation of the cover with an arcuately curved passage for pulling the cover away from the trap is critical.
In case the tray is made from a synthetic resin, the tray raises problems with a view to its ecological disposal. If the tray is made from cardboard, its construction to provide lips for the satisfactory attachment of the cover to its top surface may raise problems too.
Another film sheet package is disclosed in JP UM Pub 56(1981)-5141. Also in this case, the attachment of a cover to the opening in the top surface of the package is difficult.